Specific targeting with therapeutic agents offers substantial advantages but, to date, has proven challenging. Therapeutic agents can be passively targeted with nanoparticles, like liposomes, using the enhanced permeation and retention (EPR) effect. Tumors, for example, have permeable vasculature, which provides for enhanced growth of the blood supply, and passive targeting can be utilized. Active targeting using nanoparticles with a therapeutic agent and targeting moiety can concentrate effects in specific organs, tissues, and/or cell types, reduce degradation of the therapeutic agents, and reduce the toxic effects of systemic administration of the therapeutic agent. The targeted nanoparticles can be PEGylated, which increases circulation time of administered nanoparticles. However, constructing a PEGylated nanoparticle with active targeting has proven challenging because targeting moieties must be accessible for molecular recognition but surface-accessible targeting moieties may be degraded or lost. Additionally presenting targeting moieties on the surface of a particle may decrease the ability of the particle to evade clearance systems and thus may result in decreased in vivo half-life of the nanoparticles. Further, nanoparticles with targeting molecules formulated for oral delivery must be stable in the presence of stomach acid.